Process of purifying metals.



UNITED STATES PATENT ()FFT CE.

"ISADOIR, LADOFF, OF PITTSBURGH. PENNSYLVANTA. ASSIGNOR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY A (EORPO'RA'TTON nw vENNSYLVANIA BROGESS OF PURIFYING METALS.

To. Lilo/tong, 1;. may (:0 noon/1,

lpnl nsefttlUipprop rment .in 1{recesses oi nrifying Metalsmof in' hiehflthe following llj.[ y, ,im'en ti en;relates, to processes of purilo l'j ing metals, and its ohjectifs to novide a.

i. ii

process. of re nrn' il ig absorhetl, gases from Wilt-en..|netu1s,,an(l alloys, and to thereby llll tr\t5, ,.tll{- ,Illlj'SlCitl and chcinioal proper-- ties ol castings mrule, from such n-ietals.

When molten metals and :lll are re: posed to the air, they greutlily ahsorh oxygl'rn, nitrogen and other gases, with the re suit that. when they solidi-Ty, they form spongy masses full of lilmr-holos ln orlh-i tostmbtainsolid castings, it is-necessary to remove sinl1;ahsorl ed-.gases, and, fornthis purpose, certain (leoxidizing and. clenit-rifyin ys l l stzrnegsn 'e, ,eommonly added to the m tenwfiatemah elf-ore it is cast. 1* or this purpose, it is preferable to use sllhsta'z'ices which do not co nlqinehor-intiln l) t mingle with the molten si na te but which, after having;

accomplished the removal of the occlude gases, form a slag which may be readily removed, leaving the metal substantially free both from gases and from the purifying sulistance. Boric oxid (B 0 a wellknown example of the gas-removing substances at present employed.

I have discovered that certain hasic or on saturated. metallic oxide, such as the sol oxids of titanium, tungsten, vanadium and other metals, are highly etlicient gas-removing suhstances. These basic oxids may he added to the molten metal to be purified, J

either in the form of the basic oxids them selves or mixtures of them, or in the form of a conglomerate containi-n one or more of these basic oXids-and a suita 1e carrier.

I have made the further discovery that an improved method. of treating molten metals with gasrem'ovihg substances consists in adding the gas-removing substance in the form of an intimate mixture of such substance with the metal to he purified.

. If, for example, molten copper is to be purified by means of titanium snhoxid, I

find it convenient to employ a more or less alloyed conglomerate of copper and 'Jpecificatwn of Letters Patent.

Application-filed May 11, 1814.

*ntcnted Dec. 4, 1% Serial No. 837,715..

the titanium snhoxnl. the conglomerate hcin; prcparw l in the 'l'ollmring manner. 1 lil'sl nialu' on intimate mixture ol' CUI- prons ()Xltl and titanium snhoxid, by grinding these oxiiha together, anti 1 term pellets oi this mixture. using a binder such as eater, glycerin, glucose, or the like, and dry the pellets for some time, first in tin;

air and then at a moderate heat in a suit Flllit' oven. 1 then pack the dried pellets in a (I. is reached. and the receptacle is then a lowed to cool to room temperature.

tire heating may be accomplished in alooit twenty-four hours.

The pellets are then removed from The e v 'th e purified, partial alloys of such metals with 'the suboxid ,ofa. gas-removing metal, such astitanium, may be prepared by mixing anxoxid of the metal to be purified wit the suboxid of the gas-removing metal and treating the mixed oxids in the manner just described} Thus, for the purification of iron, a. ,mixture of iron with titanium suboxidjor" other suitable suboxid, may be used, and-"similar mixtures of metallic suboxids with zinc, tin, lead and other metals maybe similarly repare'd.

When t e molten metal to be purified is an alloy, I prefer to combine the gas-removing suboxid with the chief constituent of the alloy, to be treated; the process being carried out just as I have described it in connection with the purification of single as the metals. 7

While I have described titaniumsuboxid as-removing substance to be used in carrying out my process, it is to be understood that my process is not restricted to the use of this-substance. In some instances, it is desirabletouse' metallic compounds which are capable of removing particular gases, and "in suchcases, the compounds employed may bensed in the manner described above in connection with titanium suboxid. .Forinstance, denitrifying' substances which may be so used are, the oxids of the rare earth metals such as cerium, thorium or zirconium. g

In View of the Wide" range of conditions to which my inve'ntion'is applicable, it is to be understood that no'limitations are to be .im osed unless indicated in the appended clgims.

"I claim'ns my invention:

1. The process of purifying molten metal that consists in adding to the molten metal a gas-removing substance containing titanium suboxid. 2. The process of purifying molten metal that consists in adding to the molten metal an i timate mixture containing titanium subo id mixed with the metal to e purified.

3. The process of refining copper Which consists in adding to the molten copper a substance containing a conglomerate in cluding copper and titanium suboxid and removlng the resulting slag. 4. A gas-removing agent for use in the purificatmn of molten metals comprising titanium suboxid.

531A gas-removing agent for use in thepurification of molten metals comprisin a mixture containing titanium suboxi mixed with the metal to be purified.

6. A gas-removing agent for use in the purification of molten metals comprising a mixture containing titanium subox d and an alloy containing titanium alloyed with the metal to be purified. W I y In testimony whereof, I have hereunto subscribed my name this 30th day of April,

g I SADOR LADOEF. Witnesses:

GOLDIE E. McGnn, 

